Osbourne, 27, is the son of British rocker Ozzy Osbourne and "The Talk" host Sharon Osbourne. The actor-producer and advocate for multiple sclerosiswelcomed his first child, a baby girl named Pearl, with Stelly in April 2012. The couple was engaged at the time and later married on the big island in Hawaii that following October.

"We feel so blessed that our family is growing & Pearl will have a little brother or sister to play with," Stelly added. "It's crazy to think that we will soon be a family of four!"

It's been a notable year for the Osbourne family. Ozzy and Sharon have been bouncing between split rumors and Jack's sister Kelly, a co-host of E!'s "Fashion Police," was recently engaged to vegan chef Matthew Mosshart in July.